Rename a database user or change its default schema.
Syntax ALTER USER user WITH [NAME = new_user_name] [, DEFAULT_SCHEMA = schema ] Key user Name for the user in this database. new_user_name New name for this user. schema The first schema that will used to resolve object names for user. default schema = dbo
All members of the sysadmin fixed server role have a default schema of dbo.
A user that is not mapped to a SQL Server login may connect to other databases as guest, this just requires GRANT CONNECT TO guest;
ALTER USER user87 WITH NAME = user143; ALTER USER user21 WITH NAME = user144, DEFAULT_SCHEMA = Sales;
"My friend, there are two kinds of people in the world, Those with guns and those who dig." - The Good, The Bad, and The Ugly
sp_change_users_login auto_fix,'username' - Map an existing database user to a SQL Server login.
Equivalent Oracle command: ALTER USER